A hotel I'm working with would like to have a calendar widget created in order to provide more user-friendly interface with their booking system (which is provided by a 3rd party).

In terms of functionality, the widget needs to allow user to select the check-in and check-out dates.Those dates would need to be added in a predefined link provided by the booking system provider and when the user clicks "check", it should open that link in a new tab.

Might try to get in touch with http://s-pro.io. I had a few projects done with them, it's the ukrainian dev team. They has a lot to offer if your hotel need anything else besides the widget. I had an app done in a short time, and also can say that they are really great at refactoring the code.

A hotel I'm working with would like to have a calendar widget created in order to provide more user-friendly interface with their booking system (which is provided by a 3rd party).

In terms of functionality, the widget needs to allow user to select the check-in and check-out dates.Those dates would need to be added in a predefined link provided by the booking system provider and when the user clicks "check", it should open that link in a new tab.